I just went through and updated so many pieces in some old flows. I shot myself in the foot from the beginning, so learn from my mistakes: 1) Make a copy of the whole flow before doing any update work. 2) HTTP piece updates will wipe settings, urls, fields, etc, so be prepared to copy over or redo all those settings. 3) Telegram Piece-- I've always used the custom call feature instead of the presets in the piece, so I really didn't see a benefit for updating this piece (YMMV). Patience.