According to a site named Blogjack, the circular smart cover and the pen for the Lumia 950 XL have been cancelled.
Look at point #3
???????????????? Lumia ????????? Windows 10 Mobile ?????? | BLOGJACK
This could be dismissed as just a rumor but, Blogjack correctly predicted a lot of things before other blogs.
Their leaks include ,
1) the design of the Lumia 950.(before the renders leaked) ?????BLOGJACK ?????Talkman???????? | BLOGJACK
2) the specs of the 950s before it was an "exclusive" from unleashthephones ???????????????????? 5.2 ?? 5.7 ?? 2k ?????? Lumia ?? | BLOGJACK
Look at point #3
???????????????? Lumia ????????? Windows 10 Mobile ?????? | BLOGJACK
This could be dismissed as just a rumor but, Blogjack correctly predicted a lot of things before other blogs.
Their leaks include ,
1) the design of the Lumia 950.(before the renders leaked) ?????BLOGJACK ?????Talkman???????? | BLOGJACK
2) the specs of the 950s before it was an "exclusive" from unleashthephones ???????????????????? 5.2 ?? 5.7 ?? 2k ?????? Lumia ?? | BLOGJACK