"There is no such thing as a mandated cover in the EU, all the EU says is that a product must be fit for purpose and contain no defects at manufacture."
Partly true, as I understand it. There is a mandated minimum level of protection, but that is not the same as a mandated cover and it is up to the nations to implement the directive (suitably translated) into national law. There are also other factors in determining conformity, see e.g. Article 2.2 especially 2.2 (d). DIRECTIVE 1999/44/EC Article 1 states
"1. The purpose of this Directive is the approximation of the laws, regulations and administrative provisions of the Member States on certain aspects of the sale of consumer goods and associated guarantees in order to ensure a uniform minimum level of consumer protection in the context of the internal market."
"If a product fails within six months then the burden of proof is on the manufacturer to prove it wasn't their fault, but after six months then the product is assumed to have been accepted by the consumer."
Not necessarily, at least as far as I understand it. The last statement certainly does not appear in form or intent anywhere in the directive. DIRECTIVE 1999/44/EC Article 5 states
"1. The seller shall be held liable under Article 3 where the lack of conformity becomes apparent within two years as from delivery of the goods. If, under national legislation, the rights laid down in Article 3(2) are subject to a limitation period, that period shall not expire within a period of two years from the time of delivery."
[Note the use of 'becomes apparent']
"3. Unless proved otherwise, any lack of conformity which becomes apparent within six months of delivery of the goods shall be presumed to have existed at the time of delivery unless this presumption is incompatible with the nature of the goods or the nature of the lack of conformity."
i.e. within six months, with exceptions, the fault is automatically presumed to have existed at the time of delivery, and hence coverd (practically the same as you state) - but nothing is explicitly mentioned here, or elsewhere, about the burden of proof (in some cases this is done in the national legislation as far as I understand).
The EU overview page for the legislation also says
"The Directive on Sale of Consumer Goods and Guarantees aims to harmonise those parts of consumer sale contract law that concern legal guarantees (warranties) and, to a lesser extent, commercial guarantees.
Its main element is that the seller has to guarantee the conformity of the goods with the contract for a period of two years after the delivery of the goods. Certain standards exist for assessing when conformity can be assumed and when not."
Again, here it does not state who is responsible for the proof of the causes of the lack conformity - apart from where conformity can be assumed - merely that the seller has to guarantee conformity over the period. It may be required that the consumer has to prove lack of conformity after six months, but that is not mandated, and acceptance of continued conformity after that period has nothing to do with the legislation.
In addition, the guarantee on the goods cannot be waived if it doesn't comply with the requirements of Article 6, paras 2-4 and people should be aware of the requirements in Article 7, first paragraph of which is
"1. Any contractual terms or agreements concluded with the seller before the lack of conformity is brought to the seller's attention which directly or indirectly waive or restrict the rights resulting from this Directive shall, as provided for by national law, not be binding on the consumer.|"
Further reading at http://ec.europa.eu/consumers/cons_int/safe_shop/guarantees/index_en.htm and links to the related documents (particularly interesting in parts is the report on implementation).