Suunto Vyper "Dive Attention Symbol"

I have dived tables for 10 years and just bought a Suunto Vyper dive
computer. I am confused re: the Dive Attention symbol. I have read
these groups and the comments. I have gotten this symbol and have not
violated the ascent rate. I will avoid any 'saw tooth' dives and see if
this makes a difference.

However, the manual suggest to "extend my surface interval". I cannot
find a suggested surface interval or desat time. The no-fly time is
always a least 12 hours so this does not help in planning a surface
interval before dive #2.

So my question, for you Suunto Vyper owners that have figured this out,
is 1) how do a calculate a minimum or reasonable surface interval with
the computer, and 2) when I do get a Dive Attention symbol, how long
should I 'extend' my normal surface interval to?