one way with the old el tank was to turn on and do the buffs first.
then 25 or 30 minutes later force it to do either the critter or life/item buffs again.
then from then on in it was doing about 1/2 of the total buffs every 30 minutes.
but from what you describe interrupt and rebuff. Nope about the only thing that does that is one of those combat macro programs el/life-tank. Every other buffing program i know of, is manually kicked off some come with warnings (buff me) 9 minutes, 4 minutes left so not hard to find a safe spot at 9 or 4 or begin looking for one to then start the rebuff.
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Ag Nar
Portal Mule Master of the Loresraat
Mastering the pixels of gamedom, 1 MMORPG at a time..