Some Apple Watch owners seeking a repair may be about to get very lucky. It seems Apple is running low on Series 3 smartwatches, so if a Series 3 repair ends in a replacement being required, customers may walk out the store with a Series 4 instead.

As 9To5Mac reports, Apple sent out a memo to staff this week informing them that inventory of Series 3 watches is very low, which means any customer requiring a repair or replacement would likely be required to wait. As Apple prides itself on good customer service, rather than wait, a decision has been taken to use the more readily available Series 4 inventory instead.

The knock-on effect of this decision is that if you take a Series 3 into an Apple Store or one of Apple's Authorized Service Providers for repair, chances are you could leave with a new Apple Watch Series 4. More specifically, a Series 3 Stainless Steel (GPS + Cellular) will be replaced with the equivalent Series 4 model.

If you've been putting off taking your Series 3 Watch in for repair, now is the time to do it as the inventory may not be constrained for much longer. Depending on the state of your Series 3 and what the repai solution is, you could be in line for a free upgrade.

When PCMag reviewed the Apple Watch Series 4, we concluded that although it's expensive and doesn't have built-in sleep tracking, it still "delivers a category-leading smartwatch experience with more advanced apps and health features than the competition." Getting one as a repair replacement would negate the expensive downside, obviously.