Hi All,
It seems my Design Studio lives its own life. 
So, I have DS 16.0.5, Analysis for Office 2.2 SP1, SAP BW 7.31 SP16, BI Platform 4.2 SP1
BEx has a simple BW Query, Controlling Area (CA), Cost Center (CC), Cost Element (CE), Year (Y), Month (M) and Amount (A). CA, CC and Y are variables, CA and Y single-value and mandatory, CC selection option and optional.
First I have built Workbook with 3 tabs in Analysis based on that BEx Query, CA and Y are the same for all 3 tabs, CC not: 1001, 1002, 1003, 1004 for the first and second, 1003, 1004, 1005, 1006 for the third. No issues, everything looks fine. Then I have clicked the Create Web Application button, log on to my BI Platform and all three tabs are exported to DS.
Now the strange
1.1. All my tables in all three tabs have CC 1001, 1002, 1003, 1004 already in DS.
1.2. Click Edit Initial View for the Data Source 3. CC is 1001, 1002, 1003, 1004. I change it manually with Filter by InputString for 1003, 1004, 1005, 1006, preview shows everything correct. OK + create new crosstab. Nothing changes, it is still wrong.
1.3. Go to Show Prompts. CA and Y are OK, and CC is 1001, 1002, 1003, 1004. Reset them, click OK. Now I see all CC values in all three tabs
1.4. Edit Initial View for the Data Source 1. Change CC manually with Filter by InputString for 1001, 1002, 1003, 1004, preview shows everything correct. But neither OK nor OK + create new crosstab gives me the correct result, I still see all members.
2.1. I decide to change DS prompt CC for 1003, 1004, 1005, 1006. Of course, all my three tabs are showing 1003, 1004, 1005, 1006 now as well as Data Sources.
2.2. Save, click Execute locally, Browser IE11 is opened, I go to tab three and... I see that CC is 1001, 1002, 1003, 1004!!!
2.3. Check DS, close it, close browser, open and click Execute locally. Again,CC is 1001, 1002, 1003, 1004 in Browser but 1003, 1004, 1005, 1006 in DS
2.4. Copy link and open it FF browser. Again,CC is 1001, 1002, 1003, 1004.
3.1. I go to Analysis once again, check Workbook, click Create Web Application and receive again the same as in Step 1.1
What is happening?! 
Thanks and Regards,
Ekaterina