That was sweet of them. Presumably someone organised this - do you think maybe one of your old friends phoned around a few of them & got them to write letters etc and put them in a parcel? You must have been a popular ex-member of the congregation.
As others have said - that's pretty unusual ( and not really "Society approved" , as such ). Most of us whether we fade or DA / DF suddenly have total radio silence. My wife faded after a lot of congregation problems & over a couple of weeks as rumours & news got out she experienced an avalanche of 70 or more "unfriends" on Facebook etc. I think one sister wrote a letter to her to express her feelings , but that was about it. No phone calls , texts. Just a sudden , unilateral ceasing of contact. That seems to be the norm , but I guess there are exceptions.