Don't worry about losing your epg channel. It was probably just a re-named Portal channel which has been reallocated or renamed by the Astra boffins. To update your 7 day epg just go to 'All Satellites' find a channel called Portal 5 (or 6) and add it as the last channel in all of your existing groups. Then just treat this as you did with the channel named EPG Update.
Hope this helps.
H.D.