Just as dealers yesterday were preparing to head off to the pub, up popped an announcement from Tullow Oil. If there was any annoyance on trading desks at the lateness of the statement, then they could console themselves with the fact that the blue-chip explorer's day wasn't exactly going to plan.
A rather red-faced Tullow admitted that while chatting to investors in the Kenyan capital Nairobi on Friday it had accidentally let slip an update on the progress of its Ngamia-1 well in the country.
Quickly realising the mistake, the group rushed out a clarifying statement. In it, Tullow revealed that the latest drilling of the well, which has already discovered black gold, had now found oil and gas reservoirs at a depth of between 1,800 metres and 1,940 metres.
Although it was quick to caution that the well would take another three weeks to be completed, the reaction was positive as – with Fox-Davies Capital's Alexander Ogbechie saying the update "surely bodes well for shareholders" – the stock spurted up 32p to 1,395p.
A choppy week ended with the FTSE 100 edging up just 1.48 points to 5,351.53 as positive consumer confidence figures from the States countered the news that shares in the Spanish bank Bankia had been suspended.
Lloyds and Royal Bank of Scotland did not get off quite so lightly, however, with their shares dropping 1.11p to 25.8p and 0.57p to 20.87p respectively.
In the wider financial sector, Exane BNP Paribas' Andy Hughes had some recommendations for Aviva.
The insurer has already promised to get rid of underperforming parts of the company, and Mr Hughes suggested it should package its Asian businesses together with its eastern European operations and float them, estimating such a collection could be worth more than £2bn.
The analyst also claimed that Aviva's share price had fallen too far and recommended buying the stock, despite warning that the City's earnings forecasts were too high while he expected the dividend to be cut.
In response it touched a high of nearly 279p during trading, although by the bell it was just 0.4p ahead at 268.4p.
Meanwhile, rival Admiral was doing even better, shooting up 32p to 1,116p to take top spot on the benchmark index amid optimism over whiplash claims.
Those who are hoping that Glencore will improve the terms of its all-share merger with Xstrata will not have been cheered by the latest thoughts from analysts at Liberum Capital.
Saying they still believed the chances of the commodities trader (5.35p worse off at 340.65p) upping the offer were low, they added that there were now "larger downside risks for... shareholders in the increasingly unlikely event that the deal is voted down" as the Anglo-Swiss miner dipped 22.4p to 912.6p.
On the leaderboard, support from HSBC's scribblers – who decided that Aggreko was now worth buying – saw the temporary power supplier spark up 50p to 2,157p. Another being helped by positive broker comment was United Utilities, with the water firm gushing up 6p to 643.25p after analysts from both Nomura and Barclays raised their target prices, to 715p and 665p respectively.
On the FTSE 250, Cape suffered a torrid reaction to the news it was taking a one-off £14m hit on a huge liquefied natural gas project in Algeria. With the sum worth a fifth of its adjusted, pre-tax profit last year, the industrial services group plunged 118.5p – or 36 per cent – to 205p, a level it has not seen for more than two-and-a-half years.
Another big faller was Indonesian miner Bumi. The group, which was co-founded by financier and Bullingdon Club alumnus Nat Rothschild, retreated 38.6p to 360.3p to set a new, all-time low after Nomura cut its target price to 860p, citing lower coal price expectations.
After the Scottish parliament on Thursday backed plans for a minimum alcohol price, Numis' Douglas Jack reiterated his belief Wetherspoons will be one of the biggest beneficiaries of the measure. However, this didn't stop the pub chain – founded by its chairman, Tim Martin – creeping down 1.3p to 386.5p.
On Aim, agricultural firm Agriterra raced up 0.44p to 3.9p after the penny stock revealed that the Sudanese government had agreed to pay £11.37m in compensation for work done in its previous incarnation as White Nile, the oil and gas explorer founded by former English cricketer Phil Edmonds.