Trojan used to recommend 14.4v for their FLA deep cycle batteries. Everyone did, because it was a nice safe conservative number.
HandyBob came along and said that's bull - you're better off going to 14.8v. Trojan now recommends 14.7v for the FLAs, but still recommends 14.4v for the AGMs.
Odyssey recommends 14.7v for their TPPL AGMs, but Lifeline still says 14.4v for their TPPL AGMs.
Optima's spiral-wound AGMs can goto 15v with no amp limit as long as you don't overheat them.
And, as I said, my Chinese AGMs say 14.6v-14.8v right on the case. I use 14.7v bulk/absorb simply because that's one of the factory presets on my Victron 100|30 charge controller...no monkeying around programming a custom charge profile.
For charging lead-acid - even AGM lead-acid - voltage is more important than amperage, and even so, voltage is not all that critical.
It's not a precise electronic component...it's a chemistry experiment in a plastic box. Most of the time, "close enough" is good enough.
IF you let it charge for enough hours to get the job done.