One success is required on each test. If this test fails, the two are not synched, and the operation must be repeated, from the beginning. If attained, then the two are synchronized properly. Base time is 7 days. Each extra success on the test may be used to reduce the time, one day per success.
Minimum time is one day.
The plans are easily available on Shadowland, or from your deckmeister for a reasonsable fee.