So,you had them on 5 channels.
e.g.
Say were your fixtures had addresses 10, 20, 30, 40, 50, 50, 40, 30, 20, 10
and you patched them to desk channels Ch 1 = DMX 10, Ch 2 = DMX 20 and so on to Ch 5 = 50
You then recorded cues and playbacks using these 5 channels.
So they are now addressed as 10, 20, 30, 40, 50, 60, 70, 80, 90, 100
These will need to be reflected in the patch however there are two ways to do this
You could patch them as Ch 1 = DMX 10, Ch 2 = DMX 20 and so on to Ch 5 = 50 then Ch 6 = 60, Ch 7 = 70 and so on up to Ch 10 = 100
If you do this then channels 1 to 5 will still appear in all the cues and playbacks but channels 6 to 10 will not and will have to be added to all relevant cues and playbacks.
Alternatively, you should be able to patch two fixtures to each of the existing channels as Ch 1 = DMX 10 and DMX 100, Ch 2 = DMX 20 and DMX 90 and so on up to Ch5 = 50 and 60. This would mean the show would look exactly the same but you would still have to treat the fixtures as pairs. (I know you can do this on the full FLX but I can't find it in either the full FLX or the FLX S versions of the manual)