Windows 10 will be released for desktops on the 29th of July, but many users are still puzzled about the upgrade timeframe for Windows 10 Mobile. According to a leaked OEM slide by Neowin, the Windows 10 update will be done by the end of Q3, leaving carriers to commence roll outs after testing.
A slide acquired by French tech blog Mon Windows Phone from SFR may shed more light on this. According to the slide, SFR Telecom plans to roll out the Windows 10 Update to its devices (1020,920, 925, 930, 830, 635, 625, 535, 530, 520and 435 etc)
While Microsoft has held back from offering a date, the general consensus on Windows 10 Mobile has been Q3 2015 or fall to coincide with the launch of the new flagship devices. Carriers have typically .according to SFR, Windows 10 should land either in October or in November.