this whole thing is confusing.
i meet all the requirements except having 50 rep pts. so it wouldn't have mattered if i'd repaid my subscription and been grandfathered in or not because i'd still have swap access, if i renewed now and i wasn't really interested in the rest of benefits or access that comes with a SCM. not even sure i qualified for that, i was donating at the lowest level.
the thing is, is you didn't need that many rep pts. when i joined (and i obviously didn't pay attention to the changes because i wasn't really posting in many of the forums here). i only got the email notification two days before my subscription lapsed and i didn't log on and check to see what day it would actually be, so again, i am at fault for not renewing in time but i had no idea i had to renew in time to be grandfathered into anything. i'll have to go back and read the new guidelines again because i am really confused. i know, i already said that. lol!
The confusion is probably because there are two separate issues.
I checked your account. You were not among those Benefactors and Sponsors "grandfathered" into senior community member access, as your subscription was at the supporter level. Because of this, you will have to meet the general requirements for this usergroup if you wish to access Carseat Swap this way.
The supporter subscription like the one you had still includes Swap access. So, if you renew at this level at any time, whether your subscription expired or not, you will get Swap posting access again.
The third option for changing your old swap posts is to flag them with the Report Post feature and one of the moderators can update your posts.
Unfortunately, thresholds for access to various usergroups are always subject to change. In particular, the requirements for the Senior Community Member and Carseat Guru usergroups have changed at least a few times over the years and some users were grandfathered into these groups at each change. The most recent changes were primarily due to privacy concerns.
While it is possible these requirements will change again in the future, I believe the current levels will probably remain for some time unless there is widespread abuse of the reputation system or inflating post counts.