Ridsdale, advisor to PNE owner Trevor Hemmings had detailed talks with Frankie McAvoy and the coaching staff at the end of last week about squad strengthening.
No definite figure has been put on how many incoming deals North End will do but there is plenty of scope for new arrivals.
They can have 25 players aged 21 and over registered with the EFL.
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Players under 21 don’t count towards the quota unless they are on loan.
At the moment, the Lilywhites have 23 contracted players who count towards the 25-man limit.
In addition they have seven players under the age of 21, including the four who were given professional contracts last week.
Ridsdale told the Lancashire Post: “Normally May is really quiet, things tend to pick-up in June.
“This year it has been mad with more players either being released or being made available because of financial constraints.
“We had a meeting on Friday – Frankie, Paul Gallagher, Steve Thompson and myself – about where we need to do work in the squad.
“There’s plenty to consider, some of it will depend on which of the players we had on loan will return.
“Then there are the players who were on loan at other clubs who have come back.
“We will look at what they want to do.
“Of the five loan players we had here, there is a chance that three could come back.
“Daniel Iversen we have asked Leicester about.
“We will see if Liverpool want to let Sepp van den Berg out again.
“Liam Lindsay played well and did a job here, so that’s one to consider.”
Whoever is in the Preston squad next season will pull on a shirt with a new sponsor on the front.
In a statement released on the official website, Ridsdale confirmed a ‘non betting’ partner would have their logo on the shirts.
The company in question will replace 32Red whose sponsorship contracthas come to an end.
North End signed a deal with 32Red in 2018, initially for two years with another year’s option – which was taken up last summer.
Having a betting company as shirt sponsors has not fitted comfortably with some fans.
When 32Red, Tempobet and 888 have been shirt sponsors, junior replica kits have had to carry a different logo due to gambling rules relating to Under-18s.
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