I have been taught that living in all three sides of the triangle of sobriety, recovery, and unity will keep you sober.
One excellent opportunity for people to do service is at meetings, which require a lot of work.
A friend of mine from the US, who recently relapsed, has had to give up all of his service assignments because he no longer has the 90-day requirement, which, in the city in which he lives, is a requirement for any service at all, at least in the groups he is aware of.
At my home group, we do not have a 90-day requirement. This means very new people get to greet, make tea, set-up chairs, wash up cups after, and set out literature. We obviously would not give the role of secretary or treasurer to someone new. But someone new can perform these tasks quite well.
Occasionally there is some unreliability with newcomers, perhaps a little more than with people who have been sober for longer, but any exposure to AA over a considerable period of time will reveal that unreliability is by no means the preserve of people with less than 90 days.
Provided that the group is well organised, a no-show causes little or no genuine disruption anyway.
If you are new in AA, it is likely that other areas of your life are very messy or non-existent. It may well be that the only place where you have an opportunity for service is in AA itself. That was true for me when I was new.
I am grateful that I was afforded the opportunity from day 1 to be of service, and I had three or four service assignments a week from the beginning. This made me feel part of AA and made me feel useful and needed for the first time in a long time. It was the beginning of real spiritual recovery: I could be there for others. The time I was doing service was sometimes the only time I was not thinking about me.
The Big Book of Alcoholics Anonymous also suggests a turning outward to service and throughout emphasizes the danger of delay and the importance of prompt action. In the Chapter A Vision For You, Bill and Bob immediately start working with others.
Where I go to AA, newcomers get into service straight away and as sponsor as soon as they are asked, provided that they are well through the Steps, regardless of how long they have been sober.
There are no 90-day requirements for service.
There are no 1-year requirements for sponsorship.
If you are a real alcoholic in real trouble, you do not have that kind of time to hang around.
A quiet plea to those parts of AA where artificial rules are imposed: do not keep the solution from the people who need it the most.