Presumably she died on 15 August last year and that’s not a typo for 15 July this year
If he will not let you see what is in the will then you can get a copy from the probate Registry for £6
There are various grounds for contesting probate and these are the family member doesn’t make a provision for you as in your case, you can bring a claim under the Inheritance (Provision for Family & Dependents) 1975.
Undue influence: if you think that your brother had twisted her above his mind to put in the well what he didn’t really want
if you lack mental capacity and finally fraud.
There are strict timescales and these are 6 months for a claim under the Inheritance Act and 12 months for claims of undue influence or lack of mental capacity.
Hence, you have left it really late to challenge the will.
Unless you have experience of issuing such proceedings, you may need to see a solicitor really quickly to get proceedings issued even though you may not present them to your brother. You then have three months to put a case forward to contest the will.
I cannot impress enough, the urgency of this if you want to make sure that your brother doesn’t keep everything.
Can I clarify anything for you?