tmux 2.1 vs 2.2 default socket path

gistfile1.txt

jyotty@pleione:~$ tmux list-sessions 
0: 1 windows (created Mon May 16 14:29:38 2016) [121x58] (attached)
2: 1 windows (created Thu Jun  2 10:26:19 2016) [100x29]
jyotty@pleione:~$ brew update && brew upgrade tmux
…
🍺  /usr/local/homebrew/Cellar/tmux/2.2: 9 files, 639.4K
jyotty@pleione:~$ tmux list-sessions 
error connecting to /private/tmp/tmux-501/default (No such file or directory)
jyotty@pleione:~!$ ps aux|grep tmux
jyotty           2719   0.0  0.0  2461140   1168   ??  Ss   16May16   1:57.13 tmux
jyotty           2717   0.0  0.0  2446804    112 s000  S+   16May16   0:00.01 tmux
jyotty          22557   0.0  0.0  2434840    768 s015  S+   10:27AM   0:00.00 grep tmux
jyotty@pleione:~$ lsof -p 2717
COMMAND  PID   USER   FD   TYPE             DEVICE  SIZE/OFF    NODE NAME
tmux    2717 jyotty  cwd    DIR                1,5      2754  630529 /Users/jyotty
tmux    2717 jyotty  txt    REG                1,5    451116 2350686 /usr/local/homebrew/Cellar/tmux/2.1/bin/tmux
tmux    2717 jyotty  txt    REG                1,5    218176 2350556 /usr/local/homebrew/Cellar/libevent/2.0.22/lib/libevent-2.0.5.dylib
tmux    2717 jyotty  txt    REG                1,5    639664 8395923 /usr/lib/dyld
tmux    2717 jyotty  txt    REG                1,5 558292478 8403599 /private/var/db/dyld/dyld_shared_cache_x86_64h
tmux    2717 jyotty    0u   CHR               16,0 0t5302319    1133 /dev/ttys000
tmux    2717 jyotty    1u   CHR               16,0 0t5302319    1133 /dev/ttys000
tmux    2717 jyotty    2u   CHR               16,0 0t5302319    1133 /dev/ttys000
tmux    2717 jyotty    3u  unix 0x8e0f9af7754ed36b       0t0         ->0x8e0f9af76ef9ed8b
tmux    2717 jyotty    4u  unix 0x8e0f9af76ef9ed8b       0t0         ->0x8e0f9af7754ed36b
tmux    2717 jyotty    6u  unix 0x8e0f9af7754ebf1b       0t0         ->0x8e0f9af76ef9ff83
jyotty@pleione:~$ lsof -p 2719
COMMAND  PID   USER   FD   TYPE             DEVICE  SIZE/OFF    NODE NAME
tmux    2719 jyotty  cwd    DIR                1,5      2754  630529 /Users/jyotty
tmux    2719 jyotty  txt    REG                1,5    451116 2350686 /usr/local/homebrew/Cellar/tmux/2.1/bin/tmux
tmux    2719 jyotty  txt    REG                1,5    218176 2350556 /usr/local/homebrew/Cellar/libevent/2.0.22/lib/libevent-2.0.5.dylib
tmux    2719 jyotty  txt    REG                1,5    639664 8395923 /usr/lib/dyld
tmux    2719 jyotty  txt    REG                1,5 558292478 8403599 /private/var/db/dyld/dyld_shared_cache_x86_64h
tmux    2719 jyotty    0u   CHR                3,2       0t0     304 /dev/null
tmux    2719 jyotty    1u   CHR                3,2       0t0     304 /dev/null
tmux    2719 jyotty    2u   CHR                3,2       0t0     304 /dev/null
tmux    2719 jyotty    3u  unix 0x8e0f9af76efa0a73       0t0         ->0x8e0f9af76ef9e4f3
tmux    2719 jyotty    4u  unix 0x8e0f9af76ef9e4f3       0t0         ->0x8e0f9af76efa0a73
tmux    2719 jyotty    5r   DIR                1,5      2754  630529 /Users/jyotty
tmux    2719 jyotty    6u  unix 0x8e0f9af7754ed1db       0t0         /private/var/folders/lk/_q_jq9w9667dm2v_vy4fdr740000gn/T/tmux-501/default
tmux    2719 jyotty    7u  unix 0x8e0f9af76ef9ff83       0t0         ->0x8e0f9af7754ebf1b
tmux    2719 jyotty    8u   CHR               16,0 0t5302319    1133 /dev/ttys000
tmux    2719 jyotty    9r   DIR                1,5      2754  630529 /Users/jyotty
tmux    2719 jyotty   10r   DIR                1,5      2754  630529 /Users/jyotty
tmux    2719 jyotty   11u   CHR               15,7 0t3508949     571 /dev/ptmx
tmux    2719 jyotty   15r   DIR                1,5      2754  630529 /Users/jyotty
tmux    2719 jyotty   16r   DIR                1,5      2754  630529 /Users/jyotty
tmux    2719 jyotty   17u   CHR              15,16      0t89     571 /dev/ptmx
jyotty@pleione:/private/tmp$ tmux -S /private/var/folders/lk/_q_jq9w9667dm2v_vy4fdr740000gn/T/tmux-501/default a
[detached (from session 2)]