I think Jaqen will spare Arya and let her go once the Waif gets to her again. He specifically told her before she left to get Arya not to make her suffer. Don't allow her to suffer. Stabbing her in the stomach several times instead of making her death quick is essentially making someone suffer. So I think he's going to make the Waif pay for that with her own life. And Arya will be on her way to Westeros by the end of this season. I think once the battle of Winterfell is complete the season will end with Jon and Sansa restoring order and fortifying the North. Cersei and the Lannister's will work on regaining King's Landing and restoring order there and preparing to march on the North. And then it'll cut to Daenerys either sailing for Westeros or at least meeting the Greyjoy kids. Arya I think makes it back to see Jon. Melisandre already told her once that they would meet again. I think that's a good sign she'll make it back at some point to be reunited with Jon and Sansa. I think Rickon dies this year though. Ramsay will flay him and put him on the battlefield as a burnt offering to entice and enrage Jon. 

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