New character limitations in email aliases

Ma ha preguntado...
hi all, until recently I used dot in my email aliases. e.g. xxx.yyy@riseup.net. But since a couple of days if I try to create an alias with dot I get an error "alias xxx is invalid". If I replace the dot with another character it works. Are there any character limitations for email aliases?
Thank you for a response.
Cheers
Votos positivos | 1
Ma ha contestado...
my last post just vanished, apologies any double entry
Votos positivos | 0
Cyanolyca turcosa ecua4944
Urraca De Cuello Negro ha contestado...
closing this in favor of #6069
Votos positivos | 0