As Wales' Covid-19 vaccine rollout continues, attention has turned to jabbing those who are aged between 18 and 49.
The Welsh government previously said it would offer all eligible adults a first dose of the vaccine by the end of July.
However, for those waiting who wish to book a jab as soon as possible, the situation may differ depending on which health board area you live in.
For example, some health boards have set up reserve lists, which some people can apply to be put on in case there are any leftover doses.
Betsi Cadwaladr health board said it might vaccinate some under-30s before older people, depending on supplies, after it was announced those aged between 18 and 29 would be offered an alternative to the Oxford-AstraZeneca jab.
Dr Emma Yhnell, 30, from Cardiff, was one of those who was able to receive their jab after placing herself on a reserve list.
She said she the form took "a few clicks" to fill out and she was called less than 24 hours after signing up for the list.
"It was a private number calling me and I almost didn't answer thinking it may have been a spam call, but I am glad I did.
"I never thought I would get called up so quickly, but as soon as I was offered I felt it was so important so was delighted to book in the appointment."
Lawrence Dixon, also 30 and from Cardiff, had a similar experience to Dr Yhnell.
He said: "I saw a link on social media and signed up in the morning and then that evening I got a call to say a slot was available."
He was eating his dinner when he was told there was a space at the vaccination centre and to come down in 30 minutes.
"I just signed up on the off chance, I know a few people who have signed up but not been called. I guess I was just one of the lucky ones.
"When I got to the centre, no-one said anything about my age, I gave my name and got the vaccine. Everyone in there were in the age category that are currently getting vaccinated. I saw one other person around my age."
Cardiff and Vale health board said 51% of 40-49-year-olds had now had their first dose of the vaccine, and it was now inviting people in their thirties to have their jab.
It said it had a reserve list in place to make sure no vaccine was wasted - such as if people do not show up - which anyone over 18 could sign up for.
"Once details are entered individuals will be contacted in chronological order - oldest first when an appointment is available," it said.
What is the vaccine advice in my area?
In its latest vaccine update, Aneurin Bevan health board, which covers Blaenau Gwent, Caerphilly, Monmouthshire, Newport and Torfaen, said it had started vaccinating people aged between 40 and 49.
It added anyone in this group should have received an appointment letter by the end of next week.
Anyone over 50 who has not been given an appointment can fill in this form.
It has not said whether it is operating a reserve list.
Betsi Cadwaladr health board, which covers all of north Wales, said it had offered a jab to everyone aged 50 and over.
For those still waiting, the health board said it would send out invitations to the remaining population based on the deliveries of vaccines it receives.
This means some people aged 18 to 29, who will be offered an alternative to the Oxford-AstraZeneca jab, may be offered vaccinations before some older people.
Ysbyty Enfys, in Bangor, said it had invited 28 and 29-year-olds for their injections this week in order to use up the hospital's available supply of the Pfizer-BioNTech vaccine.
The health board said it expected to receive its first doses of the Moderna vaccine from late June.
Anyone over 50 who has not been contacted has been urged to complete an online form and an appointment letter will be sent in the post.
Cardiff and Vale health board said it was ahead of schedule and was inviting people in their thirties for a jab.
It said all those in their forties had now been given appointments, and 51% of the group had received their first dose.
It has also set up a standby list, where anyone can sign up, if doses become available at short notice, it will be "oldest first when an appointment is available", the health board said.
Anyone in priority groups one to nine - over the age of 50, care workers or NHS staff, or anyone with an underlying health condition which puts them more at risk - who has not been invited for a first dose should contact the health board.
"We do not advise people turning up at any of our sites without an appointment as this adds additional pressure to the service and our staff", the health board said.
Cwm Taf Morgannwg health board, which covers Bridgend, Rhondda Cynon Taf and Merthyr Tydfil, said it was still working through giving first and second doses to people in priority groups one to nine, which includes any adult over 50, or those with underlying health conditions who are over 16.
People aged between 40 and 49 are now also being invited for vaccinations.
The health board has opened a reserve list, which on Tuesday expanded to include those who are 35 and over.
Those 50 and over who have not yet been contacted about a first dose can fill out a form.
Hywel Dda health board said it was still administering vaccines for those in priority group nine.
It said appointment letters for those aged 40 to 49 would be issued from Thursday, with appointments for this group starting on Monday.
A reserve list has not been set up for anyone aged 49 or below, while the health board tries to allocate appointments to those who are in priority groups one to nine who may have missed their jab.
It asked anyone who is over 50 or aged between 16 and 64 and living with an underlying health condition, who is yet to receive their first dose, to contact the health board by emailing: COVIDenquiries.email@example.com
People in Powys aged between 30 and 39 are being called for their jabs, with two thirds of people aged between 40 and 49 already having their first dose.
There are two reserve lists for anyone under 40 who wants to receive their vaccination.
The first is for people between 30 and 39 who have yet to be contacted, while the second is for those between 18 and 29.
A form is available for anyone over the age of 40 who has yet to receive their invitation for their first dose.
Swansea Bay health board is sending out vaccine invitations to people over the age of 40.
The health board is also running a reserve list for anyone over the age of 18, who can come at short notice, to use up any spare vaccine doses which are left over at the end of the day.
Anyone who is over the age of 50 and has not yet had an appointment should email the health board at: firstname.lastname@example.org