Avatar's Favor And 500+ Skill

Question is simple: is there a new tier for Avatar's Favor at 500(+) summoning magic skill, like for most magic skills?

Both Wikis state 447+ skill, but I am wondering.

My question is similar enough to this to feel the need not to start a separate thread... I've looked on various FFXI sites to see what the perks are for Summoning Skill above 500, and I'm not finding much... My current skill level is 511, and I'm just wondering if there's any need to go higher? Does anyone know if the potency of Blood Pact: Wards still increase with new tier levels at this point, or does it eventually cap and just the duration is lengthened?

Thanks

I'm mostly interested in Blood Pact: Ward potency like Earthen Armor... I was 495 skill, then changed some merits around and got my skills up to 511, and I can see some of the Wards are lasting longer (like 8-9 seconds longer), but I wasn't sure if their potency was enhanced as well at this high of a level.