Furthermore, the Channel Central should utilize the IBL, IEL, IIL, IQLs respectively if they are deemed synchronized.
I would dare to claim that it already does that. When you open the channel central second time you likely notice that mIRC will not request /mode #chan +b anymore and fills the banlist from the IBL instead.
I would rather propose that just as mIRC fills IAL on join it should fill the IBL (and IEL, IIL, IQL) as well.
Im not sure what the reason for not filling the IBL on join is (Could it be to avoid possible lag on join?) but right now $chan($chan).ibl stays $false unless you specifically "force" mirc to fill it. And thus only bans in IBL will be the bans that mIRC has seen (eg. bans that have been set after you join the channel).
That also makes
if (v1 isban v2) unreliable unless you specifically force IBL to be filled.
