I wouldn’t call 20 APs a “huge” network 
but anyway, if they all have the same config (as they should, except identity), you can automate any number APs and chages via a simple bash script and a “for” or “while read” loop and some ssh - been there, done that for about 150 Mikrotiks spread around the coutry in one go 
Bigger problem IMO is that those AC devices are not very stable in some cases (https://forum.mikrotik.com/t/access-points-with-kernel-failure-im-going-crazy/). Btw, with 7.22beta1 I saw 3 reboots of a hap ac3 that I have upgraded for testing. Most stable version is still 7.13.5 but even with that there are kernel failures, only not so often.