What steps will reproduce the problem?
This situation happens to Pandaren characters
It happened to 2 of 3 my Pandaren characters, and 1 of my friend's Pandaren characters.
one is level 14 Monk, one is level 92 Priest and the other one is level 100 Rogue.
(But it didn't happen to my level 90 Monk at the other server)
It happens since I logged into the world.

What is the expected output? What do you see instead?
When I open the window of BankItems, there are only 1st bag of inventory.
No other bags and no equipped items or other things been recorded.

What version of the product are you using?
r240

Do you have an error log of what happened?
        {
            ["message"] = "Interface\\AddOns\\BankItems\\BankItems-r240.lua:3716 attempt to index field '?' (a nil value)",
            ["time"] = "2015/10/11 01:04:29",
            ["locals"] = "self = BankItems_Frame {\n 0 = <userdata>\n}\nevent = \"PLAYER_ENTERING_WORLD\"\narg1 = nil\nbagsToUpdate = <table> {\n 1 = true\n 2 = true\n 3 = true\n 4 = true\n 5 = true\n 6 = true\n}\nBankItems_UpdateFrame = <unnamed> {\n 0 = <userdata>\n}\nstrfind = <function> defined =[C]:-1\nisBankOpen = false\nbankSlotsToUpdate = <table> {\n}\ndontUpdateClosedBank = false\nisVoidReadable = false\n",
            ["stack"] = "Interface\\AddOns\\BankItems\\BankItems-r240.lua:3716 in function `BankItems_SaveInvItems'\nInterface\\AddOns\\BankItems\\BankItems-r240.lua:1173 in function <Interface\\AddOns\\BankItems\\BankItems.lua:1152",
            ["session"] = 8143,
            ["counter"] = 156,
        }, -- [1]

Please provide any additional information below.