In my opinion it's a bug. However no matter what I do I can't reproduce this behavior. 
 
I've tried with a clean FlashFXP.ini and my results are totally different. 
 
After connecting to site C, site B will list and then Site C will list. 
 
[08:50:56] [L] QUIT 
[08:50:56] [L] 221 Come back soon! 
<--- Disconnect site A 
[08:50:56] [L] Logged off: 10.1.1.20 
[08:50:56] [L] Connecting to File Server -> IP=10.1.1.50 
[08:50:56] [L] Connected to File Server 
....... 
[08:50:56] [L] CLNT FlashFXP 3.3.7.1131 
[08:50:56] [L] 200 Noted. 
<--- Site C logged in 
 
[08:50:56] [R] TYPE A 
[08:50:56] [R] 200 Type set to A. 
[08:50:56] [R] PROT P 
[08:50:56] [R] 200 PROT command successful. 
[08:50:56] [R] PASV 
[08:50:56] [R] 227 Entering Passive Mode (10,1,1,50,234,197) 
[08:50:56] [R] Opening data connection IP: 10.1.1.50 PORT: 60101 
[08:50:56] [R] LIST -al 
[08:50:56] [R] Connected. Negotiating TLSv1 session.. 
[08:50:56] [R] 150 Data connection accepted from 10.1.1.10:4630; transfer starting. 
[08:50:57] [R] TLSv1 negotiation successful... 
[08:50:57] [R] TLSv1 encrypted session using cipher AES256-SHA (256 bits) 
[08:50:57] [R] 226 Transfer ok. [Free: 1.606 GBytes] 
[08:50:57] [R] List Complete: 403 bytes in 0.05 seconds (8.4 KB/s) 
<--- Site B refreshed listing 
 
[08:50:57] [L] PWD 
[08:50:57] [L] 257 "/" is current directory. 
[08:50:57] [L] MKD /RichVideo 
[08:50:57] [L] 257 "/RichVideo": directory created. 
[08:50:57] [L] CWD /RichVideo 
[08:50:57] [L] 250 CWD command successful. "/RichVideo" is current directory. 
<--- Site C makes dir, etc
		 
		
		
		
		
		
		
		
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