[Scip] Scip 3.1.0 is much more slower than 3.0.2

[Vladimir VV]

Dear SCIP team,
I was surprised when found than last version of Scip works more slowly
than previous 3.0.2 did.
For example, the same MILP problem of the following dimensions (from
scipampl log):
"... 134 variables (114 bin, 0 int, 0 impl, 20 cont) and 1159 constraints"
has been solved by SCIP 3.0.2 in ~170 sec.
"Solving Time (sec) : 169.58
Solving Nodes      : 210199
Primal Bound       : +8.38888888888988e+00 (51 solutions)"
and by SCIP 3.1.0 in ~900 sec.
"Solving Time (sec) : 891.05
Solving Nodes      : 3333047
Primal Bound       : +8.38888888888929e+00 (41 solutions)
Dual Bound         : +8.38888888888929e+00"

Both solvers had run with the default parameters settings at the same host.
But looking at solvers' outputs I see that 3.1.0 processes the search
tree completely differently than 3.0.2 does.

The same effect I see with many other problems... What is the reason of that?
-- 
Vladimir V. Voloshinov,
Ph.D, head of lab. C-3 "Distributed computing algorithms",
Center of Distributed Computing, http://dcs.isa.ru, Institute for
Information Transmission Problems RAS, http://www.iitp.ru