Ireland squad members Stephen Ferris, Craig Gilroy and Paul Marshall have been released for this Friday’s game against Edinburgh at Ravenhill (7.05pm).
Eleven other Ulster players will remain with the Ireland set up as they prepare for the Autumn Internationals against South Africa, Fiji and Argentina.
Ruan Pienaar will also be available for the RaboDirect PRO12 clash this weekend, before joining up with the Springboks squad next week.
Fellow South African Robbie Diack has recovered from a knee injury and could play his first game the opening weekend of the season.
Uncapped prop Ricky Lutton, Neil McComb, Niall Annett, Rob Herring and Ali Birch are also added to the extended group of forwards.
The backs will have a youthful look on Friday night with 6 of the 12 backs named in the 27 man squad having five caps or less to their name.
Michael Heaney, Stuart Olding, Peter Nelson, Mike Allen, Chris Cochrane and Ricky Andrew have all been included.
Ulster Rugby has already won 8 from 8 competitive fixtures this season and will look to extend that run against the Scots, before the competition takes a break for two weeks.
Provisional Ulster Squad:
Rob Herring, Nigel Brady, Niall Annett, Callum Black, Ricky Lutton, Adam Macklin, John Afoa, Lewis Stevenson, Neil McComb, Mike McComish, Stephen Ferris, Robbie Diack, Ali Birch, Roger Wilson, Nick Williams.
Paul Marshall, Michael Heaney, Ruan Pienaar, Niall O’Connor, Stuart Olding, Paddy Wallace, Michael Allen, Peter Nelson, Craig Gilroy, Chris Cochrane, Jared Payne, Ricky Andrew.
Unavailable for selection:
Rory Best, Tommy Bowe, Tom Court, Darren Cave, Chris Farrell, Declan Fitzpatrick, Iain Henderson, Chris Henry, Paddy Jackson, Luke Marshall, Paddy McAllister, Johann Muller, Andrew Trimble, Dan Tuohy.