Regarding the history of Lathander and Amaunator in the Forgotten Realms, what is the "Deliverance"?

Question

I am DMing a homebrew campaign, and I am developing a subplot related to the cleric's background. This subplot involves the gods Lathander and Amaunator.

I am mainly interested in the Dawn Cataclysm and in how Lathander acts for the greater good without considering the consequences (as written in Faith and Pantheons, 3rd Ed., page 37). I have read some materials and answers about the past of the two gods (Three-Faced Sun heresy, Risen Sun heresy, Post-Spellplague Era, and Post-Second Sundering).

However, I have not been able to find more information about the "Deliverance", other than a mention in Faith and Pantheons (page 38) and in the Forgotten Realms wiki page for Amaunator (which cites that book). I've also searched in the Sword Coast Adventurer's Guide, but there is scarce information about the Faerun pantheon.

My thought is that the "Deliverance" is some sort of omen that anticipated the facts of the Post-Spellplague Era, but I would like to have confirmation of this guess.
Does anyone have updates or information about what the Deliverance is?

I know I can do whatever I'd like since it's my own game, but I'd like for it to be as coherent as possible to the biggest events of the Forgotten Realms campaign settings, and this "Deliverance" thing seems to be a big one.

Answer 1

Deliverance is described in the novel Shadowstorm by Paul S. Kemp. Quoting:

The Risen Sun heresy had originated months ago and spread like wildfire among many of Lathander's clergy ... The heretics asserted that the Deliverance, an event in which the Morninglord would remake himself as the ancient sun god Amaunator, was imminent. The heretics ... presumed [that the Deliverance] would not only remake Lathander but also usher in a new era of worship and hope, ... They wanted Lathander to change the world for them, rather than changing it themselves in Lathander's name.

The novel describes events that take part in 1374DR and was released in 2007. We know that in the then-upcoming 4e, WotC would indeed merge Amaunator and Lathander. Had the 4e been a commercial success, Deliverance would perhaps be a name for (events happening during) the Spellplague amongst Amaunator faithful even today, but thankfully WotC backtracked in 5e, using the Second Sundering.