The tech should be able to just expand the inner slide a bit by using one or two expander balls. So pretty much just a couple of minutes of "work". But even then -- as Dave said -- you're looking for trouble by pulling it out any. Most euphs just can't use that "tuning slide" for actual tuning, though it's quite useful for water removal. On a tuba you CAN use the 2nd valve slide to tune, but that's because it's quite a bit (on BBb tubas, about twice as long) longer than on a euph. Even if the euph 2nd valve slide isn't pulled out at all, the sound of a 2nd valve slide hitting the floor in community band rehearsal is not particularly uncommon -- just from vibration/air pressure.
Gary Merrill
Wessex EEb Bass tuba (DW 3XL or 2XL)
Mack Brass Compensating Euph (DE N106, Euph J, J9 euph)
Amati Oval Euph (DE 104, Euph J, J6 euph)
1924 Buescher 3-valve Eb tuba (with std US receiver), Kelly 25
Schiller American Heritage 7B clone bass trombone (DE LB K/K10/112/14 Lexan, Brass Ark MV50R)
1947 Olds "Standard" trombone (Olds #3)