sandbox trial cycles set to 1 day but it complete very fast

[shen_ming]

I set 

{

"frequency": {

"interval_unit": "day",

"interval_count": 1

},

"tenure_type": "TRIAL",

"sequence": 1,

"total_cycles": 1

},

When I subscription.

At first     'cycles_remaining': 1  is right.

But after server minute it will be complete as    'cycles_remaining': 0 and 'cycles_completed': 1,

For my understand . It need 1 day to complete. Why it become complete so fast ?