But that hasn't stopped his efforts to strengthen the squad, with the club currently in negotiations to land goalkeeper Mike Pollitt from Rotherham.
Jewell is after a keeper to provide competition for John Filan, with Gary Walsh taking up a coaching position as well as being third choice.
If a deal for Pollitt can be struck – discussions are only at an early stage – it will hopefully start the ball rolling on the signings front.
Jewell is thought to be chasing five targets, maybe more if he has to replace any of the out-of-contract players.
Farnworth-born Pollitt is a vastly experienced keeper in the lower leagues, playing 500 senior games in a career spanning nine clubs.
He has attracted plenty of attention following Rotherham's relegation to League One, with Ipswich and Oldham linked with his services.
But at the age of 33, a move to the Premiership with Latics could be too tempting to turn down, even if he's not first choice. If a deal is to happen, it would probably be next week before it is completed as Pollitt is on holiday until the weekend.
The shortage of transfer movement to date hasn't seen Jewell panicking, even though ideally he wanted all his new faces on board before the start of pre-season training on July 1.
Jewell told the Evening Post: "I have my targets and there is some light at the end of the tunnel, although not a green light at the minute.
"Looking back at my record here, I haven't been one for getting players in too early – I would do if the right ones are available.
"If I could get my squad together by July 1, I would be delighted, but in my experience that doesn't tend to happen."
While Latics will pay the going rate for their targets, Jewell has warned they won't resort to splashing out over-the-top deals to lure players to the JJB.
That happened at his former club Bradford once they had survived their first season in the Premiership, leaving them counting the cost to this day.
Jewell said: "When it comes to a wage structure you can't be too dogmatic, but we won't be taken for a ride.
"If I said I was going to try and get Michael Owen for example, we would have to pay the going rate and no-one would complain about that.
"It's when you are paying big money to players who have maybe gone past their best and aren't producing it on the pitch, that you get a problem.
"After keeping Bradford in the Premiership a few years ago, I sat down for lunch with their chairman Geoffrey Richmond to discuss the following season.
"I said we needed some young legs in the squad while he thought we needed some more flair in there.
"It was one of the reasons I left, and Geoffrey went on to sign Carbone, Collymore and Petrescu, one for £40,000 a week and the other two on £20,000. Everyone saw what happened then."
The A-licence badge Jewell is currently working towards is a necessity for managers working in the Premiership.
Assistant manager Chris Hutchings already holds it but has to attend a refresher course over the summer.
Before setting off for the classroom, Jewell said: "I've been doing my homework with my nose stuck in the textbooks.
"I used to think I knew the game before I read them!"