It is now stated by the newly added community manager, Malarh that replays from the first beta phase won't be viewable with the next patch and phase of the beta.
When the second phase of beta begins shortly before the release of the game it will include a new patch. This patch will be removing all previous version folders. Any replays created during the first phase of the beta will no longer be viewable once the next phase begins. - Malarah, Blizzard.
This means that any replay you might want to save for later will have to be recorded unless some other solution comes up.
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