Change of employment visa rejected on applying from India

My tier 2 change of employment visa got rejected recently as I applied from outside UK citing clause 245 HBg which states-The applicant must not have had entry clearance or leave to remain as a Tier 2 Migrant at any time during the 12 months immediately before the date of the application, unless the applicant was not in the UK with leave as a Tier 2 Migrant during this period, and provides evidence to show this.
I had no clue of this clause and had to leave the country as my employer took almost 40 days to generate my CoS. I could not have waited for more than 28 days after quitting my job.
Do I stand a chance if I appeal stating my employer took more than expected time in issuance of CoS and I could not have risked staying beyond 28 days?
Any suggestions would be much appreciated.
Thanks

Decision is correct, so I don't see it being overturned.