Trawler stuck on Clifton beach: when is the next Spring tide?

So, following on from the tweets this morning after listening to Cape Talk 567, the Eihatsu Maru is still beached on Clifton 1st beach :(



So, when exactly is Spring tide and what is it?:
http://en.wikipedia.org/wiki/Tide
 

Range variation: springs and neaps
The semi-diurnal range (the difference in height between high and low waters over about half a day) varies in a two-week cycle.
Approximately twice a month, around new moon and full moon when the Sun, Moon and Earth form a line (a condition known as syzygy) the tidal force due to the sun reinforces that due to the Moon.
The tide's range is then at its maximum: this is called the spring tide, or just springs.
It is not named after the season but, like that word, derives from the meaning "jump, burst forth, rise", as in a natural spring.

So, when is the next Spring tide? 
From the table below: at 02h45 in the morning of 20th May – it will be 1,58m (compared to the 1,28m yesterday at 12h04 Tues 15th May) – that’s an extra 30cm.
http://www.koolasun.co.za/weather/tide-tables/cape-town-tides.html

See here for the latest photos of the stranded (beached) Eihatsu Maru on Clifton 1st beach via Google images and here for the latest videos.

See forum  here for nice pics (incl. pics of cable snapping again): http://www.flyafrica.info/forums/showthread.php?48730-Trawler-Eihatsu-Maru-aground-1st-Beach-Clifton/page2

Update on Fri 18th May: the trawler is now free!  They managed to get it off the sand at about 15h35 on Fri afternoon :)