unfortunately yes 
but I also get the same result from particles sim card. I get cellular connectivity but no connection to blynk
@vshymanskyy not sure if this is a blynk problem or a particle problem. When I was using particle 0.5.1-rc.1 pre release my electron was working with blynk. After it was working it was taken out of service for about a month. After trying to hook everything back up and make code adjustments the 0.5.1-rc.1 is no longer an option on the build IDE so I had to update my firmware to 5.1 After I updated 5.1 and I found blynk also had some server issues and migrated their servers and I had to update my blynk library. So after updating particle firmware to 5.1 and blynk firmware to 3.5 and writing some new code my blynk app that was working before on 0.5.1-rc.1 with blynks older firmware will not work. The error I get back from the serial monitor is invalid auth token. I know the auth token is correct as it has been verifed several times and I used the exact same code and firmware with only changed pinouts and I can connect to blynk with a photon. I have tried downgrading firmware back to 0.5.1-rc.1 but it will not work as the build IDE wont let me select 0.5.1-rc.1 as an option for building any longer it only lets me use 5.1 or 5.0 and I can not use 5.0 because that is the firmware with the original electron problem that needed fixed to begin with. Basically I don’t know if this is a blynk library issue or a particle firmware issue as it was running on a previous version of both and now will only work with a photon. Any help would be greatly appreciated I’ve been banging my head on this for a week 
@Dave1829 @Dmitriy Wow Dave, think you were spot on with your DNS update. I find it strange that both konekt and particle both have not updated their DNS. I made a clone of the blynk firmware and changed #define BLYNK_DEFAULT_DOMAIN from “blynk-cloud.com” to “45.55.130.102” and my electron is up and running smoothly. Thank you both for your help I used a combination of both of your information 
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@slimfetz glad you did it. Please don’t forget in future to switch back to host (when it will start working for you). To avoid possible problems in future.
I too am having trouble with the Particle Electron build v0.5.1 and Blynk 0.3.5 library always giving me an ‘invalid auth token’ error when looking at the logs.
I took the conclusion from @slimfetz and instead of cloning the blynk firmware, I used one of the overloaded begin methods. There is a begin method that takes the auth token, IPAddress and port. When I changed the ‘begin’ call to look like below running on the Electron started to work for me.
Blynk.begin("your auth token here", IPAddress(45,55,130,102), 8442);
obviously this is less than ideal. What needs to happen for us to use the host instead of the IP address? Where can I log a request to make that happen?
Thanks to everyone that contributed in this thread. The information here helped me figure out what was going on.
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