This is my personal opinion about above cancellation after comparing with other original, and this is my personal view. Also I am not expert so you don't have to believe me, as you have to pay for it. So please use your own judgement.
Of Course it's unique cover with India flag stamp and Gandhi stamp. When this kind of unique things happen there are more chance of forgery.
Also "Jai Hind" is printed on flag stamp, which is also mentioned on special cancellation issued on first day of 1948 Gandhi stamps.
You all know about widely forgery in private first day cover. This is more unique private first day cover with flag stamp and Gandhi stamp, so chance of forgery are very very high.
It's nothing new about forgery or BOGUS (never exist) stamps and cancellation on Gandhi stamps as well as British India stamps of King George KG stamps or King Edward or Queen Victoria.
Don't you surprised by all this FORGERY stamps.!!!
I have in my collection too.!! and I don't hope you have one in your collection too.!!
Following are some forgery blog post I wrote in past.
1911 First Aerial Mail post forgery card (one of the greatest philatelic blunder in forgery) with receiving and sending postmark.
|BOGUS forgery cancellation card of 1911 First Aerial Mail from Allahabad.|
|Gandhi Boycott British Goods label|
|Gandhi SERVICE FAKE Stamps and Governor Cancellation|
|FAKE 1948 Indian Embassy of Nepal cancellation and Independence day of India|
This is not COUNTERFEIT. It's BOGUS stamp.!! Because no country name on this.!!! (was selling from $43000 -$2000)
|FAKE Gandhi specimen stamp.!!|
|Forged 1948 Gandhi Nepal Indian Embassy Cancellation|
|FAKE 1948 Gandhi stamps "JAI HIND" Cancellation|
|FAKE Overprint Cameroun, Nicaragua stamps and FDC!!|
|How to create FAKE error stamps|
BIDDERS!! "hitlerandgandhi" just to glorify Gandhi stamps they increase price of 1948 Gandhi FDC and Used covers.!!! (Images are not enough to understand this so read following blog posts.!!)
I am not expert and I am in this hobby for 4 years only so you don't have to believe me or trust me. But you can think about it. There are more experts with 20-30-40-50 years sitting around with stamp hobby and there are expertizing certificate which might help you.
If you don't want to go through all this don't think as Investment and think as "Philately Greed" and you will be SAFE.
I think collector, dealers, seller, forger will do anything for money such as making BOGUS cancellation from Winnenden to celebrate non-violence for school shooting or plane crash cover, forged 1948 stamps, Nepal Indian Embassy cancellation, Gandhi SERVICE stamp with forged Sunday cancellation, letter reaching after 2 years or reaching in 3 days from India to France by removing stamps and black ink of rubber stamp etc.
It's nothing new. In stamp collection it has been going on 160+ years since Penny Black. But counterfeit or forgery is going on since 700 B.C. ( 2500+ years).
Gandhi Stamps Club.