Tupou, a member of the 2018 Betfred Super League Dream Team, has not played since suffering a ruptured patella tendon in June last year.
Poching revealed Tupou had a “clean up” operation on his damaged knee last week, but insisted: “Things are going well with Bill.”
He said: “It’s a minor setback for him, but we are pretty hopeful we’ve been able to solve some problems and we’re looking at hopefully [a return in] the next four or five week.”
Trinity will be lifted for tomorrow’s Channel 4-televised game at Warrington Wolves by the return of captain/stand-off Jacob Miller after he missed last week’s win over Toulouse Olympique because of concussion.
“It’s really good to have him back,” Poching said.
“He has been able to freshen up a little bit and having him back gives people around him confidence.”
The 18-6 home win over Toulouse got Wakefield off the mark in Betfred Super League, at the fifth attempt.
Poching described this week as “relaxed and enjoyable” and he said: “While we weren’t fully satisfied with the performance, to get the win means a lot and it alleviates a lot of pressure.
“We have been quite happy with our performances as a whole, but at some point you’ve got to get some reward.
“There has been a bit of a difference this week, the boys are relaxed and smiling and happy.
“That has shown in how they’ve applied themselves this week.
“I am really happy with how we’ve prepared.”
Poching, whose side return to Warrington in the Challenge Cup a week on Sunday, added: “Whatever walk of life you’re in, you work and perform better when you’re relaxed.
“Some people love the pressure, but when you are enjoying yourself and working with a smile is when you do your best work.
“Hopefully that is the case for us, we’ve got the first one and now we are able to replicate the win and put in a performance that is relaxed and full of whole-hearted effort again.”
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