  The data on hadron transverse momentum spectra in different centrality
classes of p+Pb collisions at $\sqrt{s}_{NN} = 5.02$ TeV has been analysed to
extract the freezeout hypersurface within a simultaneous chemical and kinetic
freezeout scenario. The freezeout hypersurface has been extracted for three
different freezeout schemes that differ in the way strangeness is treated: i.
unified freezeout for all hadrons in complete thermal equilibrium (1FO), ii.
unified freezeout for all hadrons with an additional parameter $\gamma_S$ which
accounts for possible out-of-equilibrium production of strangeness
(1FO$+\gamma_S$), and iii. separate freezeout for hadrons with and without
strangeness content (2FO). Unlike in heavy ion collisions where 2FO performs
best in describing the mean hadron yields as well as the transverse momentum
spectra, in p+Pb we find that 1FO$+\gamma_S$ with one less parameter than 2FO
performs better. This confirms expectations from previous analysis on the
system size dependence in the freezeout scheme with mean hadron yields: while
heavy ion collisions that are dominated by constituent interactions prefer 2FO,
smaller collision systems like proton + nucleus and proton + proton collisions
with lesser constituent interaction prefer a unified freezeout scheme with
varying degree of strangeness equilibration.
