Bell is one of the partners in developing the V-22 Osprey, which has been in service for some 17 years. Bell would be a natural for a next generation tiltrotor aircraft. Making the new craft upgradeable would be a continuation of what has been done with the V-22 and Army, Navy & Marine, and USAF aircraft. The linked article doesn't give schedule information, but it appears that the first prototype of the V-280 is toward or at the end of testing to achieve its full flight envelope. This will likely lead to a round of improvements, a build of several more prototypes ... IOW, if all goes well, including training of outfits switching to the V-280, it will likely be at least 5-10 years before the V-280 goes operational.
Osprey-bashing is a cottage industry, but IRL it will likely still be in service for at least another 10-20 years, and possibly longer.