The portal is the equivalent of your employee that turns in his notice. The ones that are not worth it hand you the notice and you let them know they don't need to give you two weeks and are done by the end of the day. The good ones hand you the notice and you tell them to keep it quiet and come back with what it will take to keep them.
Schools have 48 hours to submit the transfer application after they receive the paperwork. The ones who we know about now, either let a reporter know they submitted the paperwork or their coach didn't think they were worth saving and made the portal entry official already. There are probably high profile kids that were expected to enter that the coaches are trying to save.