Re-attempt Connecting; only works on first try?

(1) Tested this with separate it into different states - didn't work
(2) Tested with 0.7.0-rc.3 - didn't work
(2) Tested with a Particle Simcard -didn't work

With all 3 methods during the 2nd connection attempt I still get the blue+white led shown several times (with 10-15 second intervals)

Like here:

The issue I have is that Cellular.ready() never returns as True. However, this even happens with 0.7.0-rc.3 for me, not just 0.6.2 as stated before.

A suggested fix is to put the device in Deep Sleep instead, but I can't do this as this would lead to the loss of my stored variables (the device first collects data, and then connects)

I looked at my sensor data from the weekend, and out of 51 expected connections to the Cloud only 41 were made (approx. 80%). It seems to be very variable which ones don't connect; so far, all 6 have been showing some connection issues, but none of them has been totally unable to connect. The conditions are a mix of closed container w/ metal lid, closed container w/ plastic lid and open container