IOS 8 on iPad Air - captured WIFI portal page password won't reset

steps to reproduce:

a. iPad Air running IOS 8.2 (build 12D508)

b. enter credential (or just password) for WIFI portal page login

c. internet traffic flows to device normally

d. remove captured credential - continue on

e. Settings / General / Reset / Reset All Settings

f. expected result - portal page revisited asks for credential again

h. instead what happens is portal page credential is retained

i. Reset Network Settings - same result