Which is most likely to auto upgrade from SD to HD?

[sea2000]

Here's a situation I've encountered a couple of times:

A digital movie I want is only available in SD, which I generally avoid. There's no Blu-ray version. It's Movies Anywhere.

Which streaming service should I buy it from -- that is, which is most likely to automatically upgrade it from SD to HD if that pops up in the future?

Note: I realize iTunes upgrades some titles from HD to UHD automatically, and Google Play upgrades from SD and HD to UHD, but let's assume these movies aren't likely candidates for UHD.