Hi! first, thank you for this wonderful upgrade! 
I just tried this feature, with my domain name informatiquelibre.fr registered at Gandi, but it fails to push the ipv6 and mail-related records the for the main domain (the only one I set for email in/out)
2021-09-21 12:09:10,682: INFO - [#################...] > create AAAA / @
2021-09-21 12:09:13,172: ERROR - Failed to create record AAAA/maindomain.tld : list indices must be integers or slices, not str
2021-09-21 12:09:17,614: INFO - [###################.] > create MX / @
2021-09-21 12:09:19,071: ERROR - Failed to create record MX/maindomain.tld : list indices must be integers or slices, not str
2021-09-21 12:09:19,076: INFO - [####################] > create TXT / @
2021-09-21 12:09:20,375: ERROR - Failed to create record TXT/maindomain.tld : list indices must be integers or slices, not str
2021-09-21 12:09:20,412: WARNING - DNS records partially updated: some warnings/errors were reported.
The existing manually created DNS records have been deleted from Gandi DNS.
EDIT: every other records were successfully pushed, I checked on Gandi’s website.
EDIT2: I tried many times, no more luck. I guess Yunohost tries to put “@” as a subdomain but Gandi don’t allow that? I finally set those records manually.
You can read full logs here : https://paste.yunohost.org/raw/hipudusuqu
(by the way, it is just fantastic Yunohost can manage remotely DNS records!! It would really help me for some project of mine…)