The title of the episode is a reference to "Timeless Wells", the moniker given to Earth-1 Harrison Wells by Cisco Ramon after his resurrection.
Fuerza, Psych and Deon are indeed physical manifestations of the Strength, Sage and Still Forces; Deon confirmed preventing the new Forces from escaping will erase him from existence.
It's confirmed 17 days have passed since Mirror Monarch attacked.
This episode confirms that during the rebirth of the speed force, Harrison says he saw his and Barry's future selves.
Upon seeing Timeless Wells for the first time, Chester exclaims "Holy Deus ex Machina!" This is a Greek phrase, meaning 'God in the machine' and refers to the tendency for ancient Greek plays to feature gods showing up to save the day and solve problems for the main characters. In modern fiction it is used to describe a situation in which a single character, object or plot point is used to solve a problem without much effort.