Weren't Fev duel-reg with Leeds which was the arrangement of Briscoe going there then back again I believe.

He left Leeds and "signed" for Fev. Part way through the season Leeds had an injury or two on the wings and Luke was in good form for Fev, so Leeds signed him back. He was then dual regged back to Fev when he wasn't needed at Leeds anymore (and then again last season).
There were a couple of others too who signed for Fev so they didn't count as Leeds players, but then signed back for Leeds afterwards.

Warrington did it too with a few of their players, although I forget who the Championship club involved was. That was stupid enough to the point that Wire then loaned one of the players out to another club, forgetting he'd supposedly left and signed for someone else.

Briscoe signed a 3 year deal with Fev in late 2016. Around half way through that contract (June 2018) he was loaned to Leeds, although with a DR arrangement in place, before signing a permanent deal with them (Nov 2018).

Played for Fev last week in the pre-season friendly against York. He has some ability for sure but would be too far down the pecking order at Fev to stand a chance of getting regular-season game time, let alone at Leeds, so this move probably makes sense for all parties.

if I remember was the warrington player not Ryan shaw? he went to sign for somone but then agreed a loan deal from warrington to go somewhere else? seems to get a few cogs ticking

I would imagine these young lads have a super league clause in there anyway so if Leeds wanted them back after impressing in the championship, they'd be able to easily enough.

Aren't we getting two on season loans? They will have the usual re-call arrangements I'd guess.

Looks like we're DR with Hull FC https://www.hulldailymail.co.uk/sport/r ... osTo1hyVYA I spoke to a a few Fev fans on Sunday, they didn't take too kindly to me referring to them as Leeds' B team. I was apologetic for the comment, it wasn't necessary and like them, we're gonna need all the help that the rules allow this year.

Looks like we're DR with Hull FC https://www.hulldailymail.co.uk/sport/r ... osTo1hyVYA I spoke to a a few Fev fans on Sunday, they didn't take too kindly to me referring to them as Leeds' B team. I was apologetic for the comment, it wasn't necessary and like them, we're gonna need all the help that the rules allow this year.

I aren’t sure season long loans have recall options

Very few season long loans don't have recall clauses.